Art of making fastener elements



Oct. 8, 1929. G. w. BLAIR ART OF MAKING mswsumn smumm's Fi led Dec. 22,1924 i *4? 05 92 WIBZQZTI I WH mH H IIH H IIIII I Patented Oct. 8, 1929UNITED STATES.

PATENT OFFICE GEORGE w. BLAIR, or MISHAWAKA, INDIANA, ASSIGNOR 'roMISHAWAKA RUBBER & wooLEN MANUFACTURING COMPANY, or MIsnAwAKA, INDIA A,A CORPORA- 'IION or INDIANA ART OF MAKING FASTENEB ELEMENTS Applicationfiled December 22, 1921. Serial No. 757,322.

My invention relates to fasteners of the quick-operating type which aredesigned to be interlocked and released by movement of a slidertherealong, and has reference more particularly to the method of formingan elongated coiled fastener element with one or more offsets or bendsin each. convolution, which serve to afford an interlocking engagementwith another elongated coiled element.

A highly satisfactory quick-operating fastening device is obtained byarranging elongated coiled elements side by side and nesting the coilsof one of the elements be tween the coils of the other element, providedthat the nested portions of the coils of one of the elements aresuitably bent or offset so as to interlock with the coils of the otherelement. The spacing between the coils must be substantially equal tothe diameter of the wire of which the coils are formed, so that there ispractically no looseness-or play in an axial direction between theenmeshed coils of the elements, and for the purpose of holding the coilsin proper spaced relation, .the sides thereof remote,

from the points of interlocking engagement are secured to anon-stretching tape or other suitable flexible member which preventsaxial elongation of the coiled elements. In practice, it has been foundthat a particularly effective fastener element results when eachconvolution of the coiled element is provided with a plurality ofreverse bends or waves extending alternately in opposite axialdirections, as this affords a circumferential series of interlockingpoints, permitting interlocking engagement at any place therearound andmaintaining such engagement when the other element is shifted around theelement having the adjoining bends. Moreover, such formation affords abend in each convolution at the point of attachment to the tape andtends to prevent circumferential displacement of the coils on the tape.

It will be understood from the foregoing that a high degree of accuracyis required in forming the spiral elements so that the bends will alignand the proper spacing is maintained between the coils, and as the wireused in such fastener elements is necessarily small gauge, it isdesirable to avoid abrupt bends or, d1e markings which would weaken thewire and make it subject to breakage in use.

' The principal objects of my invention are to provide a coiled fastenerelement with suitable bends accurately arranged so as to afford aneffective interlocking element; to con-- struct the spring with aplurality of reverse bends or waves in each convolution which areuniform and in axial alignment; to provide a method which may beutilized for forming bends of any desired form and number in theconvolutionsof a coiled element; to avoid stamping or excessive bendingof the wire which would weaken the completed fastener element; and ingeneral, to simplify, reduce the expense of manufacture and insureaccuracy and uniformity in the con struct-ion of fastener, elements ofthe type above referred to.

On the drawings: Fig. 1 is a fragmentary view of a fastening device 'ofthe character to which myinvention relates, showing the opposed spiralelements in the interlocked and released positions respectively, belowand above the operative slider;

Fig. 2 is a fragmentary View'of rolls for crimping the wire preparatoryto forming same into a spiral coil;

Fig. 3 is a sideview of a mandrel having a coiled element thereon at thecompletion of the winding operation;

Fig. 4 is similar view, showing the coiled member on the mandrel afterthe waves or bends of the various convolutionshave been lined up; i

Fig. 5 is an end view of a finished coiled element constructed inaccordance with my in-.

ing connection therebetween and suitably operated to crimp or formreverse bends in' the wire 3. These rolls are preferably formed withspaced projections 4 somewhat 5 in the form of gear teeth, which arearranged so that as the rolls are rotated, the teeth of one roll entermidway between the adjoining teeth of the other roll,'thereby formingthe reverse bends 5 and 6 respectively, which bends, while quitepronounced, are well rounded so that no breaking strain is imposed onthe wire.

After the Wire has been crimped or formed with the bends 5 and 6 asshown in Fig. 2, the crimped wire is wound on a mandrel 7.

in any convenient manner and prefe'rabl has an aperture 8 to receive theends 0 the -crimped wire for holding the same as the winding is startedon the mandrel. Suitable mechanism is provided to direct the wire ontothe mandreland advance the same along' the mandrel as the latter isrotated so that a space occurs between successive coils which issubstantially equal to the diameter of the wire. The wire is of courseguided onto the mandrel so that the reverse bends lie flat against thesurface of the mandrel and extend respectively toward the opposite endsof or lie in a vertical plane, and providing the guidelfi which directsthe wire onto the mandrel with a horizontal slot which turns the crimpedwire so that the crimps lie in a horizontal plane as the wire feeds-ontothe,

mandrel. This uarter turning of the crimped wire and rawing same throughthe slot of the guide 16 has been found to effect a uniform opening ofthe bends andinsures proper relative positioning of the waves on thevmandrel. The crimped wire may, .of

course, be prepared previous to the winding operation and fed from aspool or other source of supply. in ,a manner to insure the requiredquarter-turn or other means may be provided foruniformly opening up thecrimps as the coil is wound.

5 The wire is preferably wound on the mandrel so vth at a plurality dfwave-like elements occur in each convolution of the wire, and itisdeslred that corresponding waves of all the convolutions shall be ar--or run somewhat ahead of the correspond- This mandrel may be arranged tobe rotated ing waves of the preceding convolution and the correspondingwaves of the convolutions are arranged in spiral lines somewhat as in-'dicated at 11in Fig. 3. After the winding of the spring has beencompleted, the final end, which is the end indicated at 12 in Fig. 3, isheld while the mandrel is turned Fig. 1 shows the manner in whichelements of this characterare intended to be used, that is, the coiledelement which has just been described, serves as a fastener element 13-which co-operates with another, fastener element 14, the latter beingpreferably a plain coil 'so that the elements 13 and 14 interlock bynesting of the coils of 'ne element between the coils of the otherelement When the slider 15 is moved therealong in one direction, andthese coils likewise release when the s ider is moved in the reversedirection. I

In the illustrated construction, each convolution of the coiled. element13 has four. bends 9 in one direction and four bends 10 in the otherdirection. However,.it is to be understood that the number of bends isnot important, as the same method of manufacture may be advantageouslyemployed toform a coiled element with a single crimp or bend of'anydesired character or extent or in fact, any number of bends.

- It will be noted that while the corresponding bends of the successivecoils run somewhat in advance of the corresponding bends of thepreceding coils, nevertheless they are sufficiently near to an axialaligning relation so that the bends of each convolution may nest withinthe corresponding bends of the ad- ]01I11I1g convolutions and'because ofthis fea- .ture, it is possible to wind the element-with pronouncedbends andat the same time have a close spacing of the coils orconvolutions.

While I have shown and described my invention in a preferred form, I amaware that various changes and modifications may be made withoutdeparting from the principles of my invention, the scope of which is tobe determined by the-appended claims.

I claim as my invention;

1. The method of manufacturing a. coiled fastener element of the classdescribed, which comprises forming bends in a length of wire at regularintervals and then winding the wire on a mandrel so that each bend-lies'flat against the surface of the mandrel and is interposed between andspaced from correiponding bends of the adjoining convolu- 1ons.

2. The method of making a coiled fastener element of the classdescribed, which comprises forming a length of wire with correspondingbends at regular intervals, then winding the Wire on a mandrel so thateach convolution comprises a bend which is interposed betweencorresponding bends of the adjoining convolutions and then untwistingthe element and thereby fixing the bends in alignment along a lineparallel to the axis of the coiled member.

3. The method of making a coiled fastener element of the classdescribed, which comprises forming a wire with a plurality of uniformlyspaced bends, then winding the wire on a mandrel so as to form anelongated coil and simultaneously stretching the wire and therebyexpanding the bends into wave-like formations with the wavelikeformation of each convolution interposed between corresponding wave-likeformations of the adjoining convolutions.

4:. The method of making a coiled fastener element of the classdescribed, which comrises forming a length of wire with uniormly spacedbends in the same plane, then winding the wire on a mandrel in separatespaced convolutions so that the bends lie flat against the surface ofthe mandrel and are offset in the direction of the length of themandrel.

5. The method of making a coiled fastener element of the classdescribed, which comprises forming a length of wire with oppositelyofi'set portions at regular intervals and then coiling the wire on amandrel so that each convolution is separated from the adjoiningconvolutions and comprises a plurality of reversely offset portions inaxial alignment with the corresponding offset portions of the otherconvolutions of the coiled element.

6. The method of making a coiled fastener element of the classdescribed, which comprises winding a wire on a mandrel in a zig zagcourse so that each convolution is separated from the adjoiningconvolutions a distance substantially equal to the thickness of the wireand comprises alternate reverse bends which are interposed betweencorresponding bends of the adjoining convolutions of the coiled element.

7. The method of making a coiled fastener element which comprisescoiling a wire with alternate bends to form an elongated cylindricalspiral spring with corresponding portions of each convolution ofisetlengthwise of the spring and with an open space between the adjoiningconvolutions substantially equal to the thickness of the wire.

8. The method of making a coiled fastener element which comprisesproviding a length of wire with interlocking means at intervals, andthen coiling the wire in the form of an elongated coiled spring with theinterlocking means substantially in alignment lengthwise of the spring,and with an open space between the adjoining convolutions substantiallyequal GEORGE W. BLAIR.

